Bus bars electrically connect terminals of electrodes of, for example, a battery module of a secondary battery.
Bus bars that connect terminals of electrodes through which a large amount of current flows need a predetermined thickness to lower electrical resistance. On the other hand, bus bars need flexibility to maintain positional accuracy of the connecting terminals in order to handle impacts or heat from the outside, and distortion due to battery swelling.
In generally used bus bars, two terminal connecting parts are provided to a plank having a thickness capable of suppressing electrical resistance, and an arcuate bend part is provided between the two terminal connecting parts. With this configuration, the generally used bus bars retain low electrical resistance and have a certain degree of flexibility.
For the above-mentioned bus bars, there may be a gap between two terminals and terminal connecting parts due to a counterforce from the terminals to the load applied to the arcuate bend part when manufacturing. To avoid such a gap, there is a need for proficiency in welding terminals to terminal connecting parts.
Accordingly, the objective of the present embodiment is to provide a bus bar with low electrical resistance, low heat generation, and sufficient flexibility that can be easily manufactured at low cost, and to provide a battery module including such a bus bar.